code: def test_protected_paths(self):
      model = init_model(key="MOD", mode="debug")
      model_version = init_model_version(
          model=model["sys/id"].fetch(), mode="debug"
      )
      with self.assertRaises(NeptuneProtectedPathException):
          model_version["sys/stage"] = "production"
  
      model_version["tmp/placeholder"] = "production"
      with self.assertRaises(NeptuneProtectedPathException):
          model_version["sys/stage"] = model_version["tmp/placeholder"]
  
      with self.assertRaises(NeptuneProtectedPathException):
          del model_version["sys/stage"]
  
      with self.assertRaises(NeptuneProtectedPathException):
          model_version["sys"].pop("stage")
  
      with self.assertRaises(NeptuneProtectedPathException):
          del model_version["sys"]
  
imports: import os
  import unittest
  from datetime import datetime
  from neptune import ANONYMOUS_API_TOKEN, Run, init_model, init_model_version, init_project, init_run
  from neptune.envs import API_TOKEN_ENV_NAME, PROJECT_ENV_NAME
  from neptune.exceptions import InactiveModelException, InactiveModelVersionException, InactiveProjectException, InactiveRunException, MetadataInconsistency, NeptuneProtectedPathException
  from neptune.metadata_containers import Model, ModelVersion, Project
  from neptune.types.atoms.float import Float
  from neptune.types.atoms.string import String
  from neptune.types.series import FloatSeries, StringSeries
label_desc: Use image node_id 17 for calling the TestExperiment obj's underlying member method code with example usage: obj.test_protected_paths() without return types